I'm running a server on a VPS, it has announce set to 1 but it doesn't show on the internet tab. The server is running 0.3DL so I don't know if that's the reason why it doesn't show.

Just ensure that your server is online, copy the adress IP AND open SA-MP? click on 'Add Server' then paste the IP properly and click enter, if the server that you're talking about is online, you will be connected succesfully, unless your internet connection isn't working . . .